Dental impression mold



May 28, 1940 L. w. EVANS DENTL IMPRESSION MOLD Filed Jan. ll, 1939ATTORNEYS Patented Mey 28, 1940 f Y 2,202,577

UNITED STATES PATENT OFFICE DENTAL IMPRESSION MOLD Louis W. Evans,Salineville, Ohio Application January 11, 1939, Serial No. 250,449

1 Claim. (Cl. 32-17).

This invention relates to dental trays and has Figure 3 is a crosssectional view taken on the for an object to provide a metallic trayhaving line 3-3 of Figure 1. rubber portions adapted to be expanded bypres- Referring now to the drawing in which like sure of hot water tosoften the dental Wax or characters of reference designate similar parts5 other material after an initial impression is made, in the Variousviews, Ill and II designate respecthese rubber portions being thereafterinflated tively upper and lower metal mold plates joined to exertpressure against the softened impression together by screws I 2 toprovide a dental tray. A material so that the same will conform to everyrubber sheet I3 is interposed between the sec cavity in the mouth andaround the gums. tions I and II and the upper section I0 is cut 1oOrdinarily after the initial impression is taken away to provide arcuateexposed portions UI of 10 the tray is removed from the patients mouththe rubber sheet around the inner periphery of and surplus impressionmaterial trimmed from the dental tray and also is cut away to providearound the edges of the tray by the dentists transverse exposed portionsl I5 and I6 of the fingers- Thel the tray iS again inserted in therubber sheet. A pair of tubes I'I and I8 are mouth and the nishedimpression is taken. This formed integral with the lower section II and15 is not entirely satisfactory as is well known since communicatesthrough ducts I9 and 20 with the the dentist must use his iingers in thepatients transverse section I6. The tubes open against mOuih. t0 DreSSthe impression material rmly the rubber sheet I3 at the initial end ofthe arcuinto the cavities and around the gums so that a ate exposedportions I4 which latter are integral true facsimile of the shape of themouth will at the rear end with the transverse exposed por- 20 beimpressed in the impression material. tion I5 of the rubber sheet.

With the above disadvantages in mind the pres A rubber bulb- 2| isprovided with a short length ent invention provides sectional moldplates of hose 22 to be interchangeably connected with J'OinedtOgeiJhel" 170 provide a tray, with a sheet of hose connections 23 and24 lcarried by the tubes 25 rubber between the sections, the upper trayhav- I1 and Is. The bulb is also provided with a short 25 ing portionsremoved to expose the sheet of rubhose 25 which may be connected to anysuitable ber. A pair of tubes disposed exteriorly of the source of watersupply. The bulb is provided tray communicate through duets in the lowerwith check valves 26 and 21 to restrict new to .tray with the exposedportions of the sheet of one direction,

30 rubber SO that hOt Water may be pumped into In operation, forsanitary reasonsapaper lining 3o the tray underneath the rubber sheet toheat Strip 28, sho-wn only in Figure 3, is placed upon the rubber andsoften the impression material the upper section Il] and then the dentalwax and thereafter the Water may be Withdrawn and or impression materia1is applied to the tray and ai? pumped through 011 0f the tubes t0inflate upon the lining in the conventional manner.

the rubber portions so that the latter will press The tray may new beinserted in the patients 35 y the 110i? iIllDl'GSSiOn. materialCompaotly against mouth and the initial rough impression taken. the gumsand against the CaViieS in the mOllth The tray is then withdrawn andsurplusv wax or WithOlll': any USG being made Of the deniists impressionmaterial removed from around the fingers. edges of the tray. The tray'isagain inserted 40 With the above and other objects in View the in thepatients mouth to take the nal impres- 40` invention consists \ofcertain novel details of sion and at this time hot water is pumped byconstruction and combinations of parts hereinmeans of the bulb 2|through the tube I'I and after fully described and claimed, it beingunderu passes through the duets IS and 2n to the transstood that variousmodiiications may be resorted verse exposed portion I6 of the rubbersheet and t0 Wi'hill the SCOpe 0f i111@ appendld Claim. Withalso passesunderneath the rubber sheet through 45 out departing from the spirit 0rsacrificing any the arcuate exposed portions I5 and through the of theadvantages of the invention. transverse exposed portions I6 of thesheet. The In theaccompanyng drawing fOTmIlg Dart 0f hot water bulges upall of the exposed portions this specication, of the rubber sheet justmentioned and the heat Figure 1 is a longitudinal sectional View Of a ofthe water is transmitted to the impression 50 dental tray constructed inaccordance with the material thereby softening the material. Theinvention and taken on the line I-I of Figure 2. hot water may now becut off and thereupon air Figure 2 is a longitudinal sectional viewtaken may be pumped into the ducts and behind the on the line 2-2 ofFigure 1 with parts in elevaexposed portions of the rubber sheet abovetraced tion. to innate the exposed portions of the rubber 55 A dentststray comprising upper and lower mold plate sections clamped together toprovide a tray, a sheet of rubber between the sections, the uppersection being out away at predetermined points to expose the rubbersheet, a pair of tubes communicating With the exposed portions of therubber sheet and adapted to selectively supply hot water or air pressurefor deforming the exposed portions of the rubber sheet to shape theimpression material accurately to the contour of the mouth and gums Whenan impression is being taken.

. LOUIS W. EVANS.

